As far as bids for immortality go, it must already be the most lucrative in history. Larry Page's restructuring of Google under a new umbrella called Alphabet - in a way designed to ensure both its longevity and his own - delivered an instant $28bn boost to the company's stock market value.

As far as bids for immortality go, it must already be the most lucrative in history. Larry Page's restructuring of Google under a new umbrella called Alphabet - in a way designed to ensure both its longevity and his own - delivered an instant $28bn boost to the company's stock market value.

As Wall Street and Silicon Valley processed what was a genuine shock to an industry long accustomed to leaks, analysts and pundits grasped for deeper meaning in the prosaic details of a corporate reshuffle. Many of the 5,000 direct staff and contractors at Google's European headquarters in Dublin were also caught by surprise, though it soon became apparent that Ireland would be completely unaffected by the changes.

The reason for the leap in market capitalisation was clear, at least. Page separated his pet projects and Google's speculative technologies - human longevity, self-driving cars and internet-connected smoke thermostats - from its core online businesses. Web search, Android, YouTube, Maps, advertising and the rest of Google's money- spinners will now report their performance separately from the loss-making units.

Even before they are told how much the company has been spending on drones and hi-tech contact lenses, shareholders effectively celebrated the prospect of having a better idea of what is going on at their company. Under Alphabet, businesses that were valued negatively as part of Google are worth closer to zero, according to Wall Street, so the shares jumped.

The move was announced to investors, in Google's traditional style, as a fait accompli. But while Page and other senior executives exercised the special power their shares hold, the age of Alphabet will be seen in some quarters as a concession to the market.

Until recently, Google's shares were flat-lining while the wider technology sector boomed. Dis- quiet on Wall Street at Page's apparent focus on sci-fi projects was growing, as analysts and investors questioned how the company would remain at the heart of the consumer internet.

Having already effectively given up social media to Facebook as a lost cause, questions were being asked about how Google's dominance of web advertising, based on desktop search, would survive the shift to smartphones and apps. On mobile, people search less, preferring to go straight to the relevant app and cutting out Google as the middleman.

At the same time, the company was suffering a brain drain. Amid the sluggish share price performance, some of Google's brightest minds were being tempted by start-ups. Long-time Google Ireland chief and veepee John Herlihy stepped down earlier this year and has teamed up with John Given's Malin biotech investment group, joining the boards of some of its investee companies.

In the context of a long-running anti- trust investigation in Europe, Google began to invite unflattering comparisons with Microsoft in the late 1990s.

Could the defining company of the web era follow the defining company of the PC era to join the technologically irrelevant ranks of Wall Street income stocks?

Page acknowledged the threat as he revealed Alphabet as his solution, saying that "where revolutionary ideas drive the next big growth areas, you need to be a bit uncomfortable to stay relevant". By divorcing the leadership of the company from its most successful business, Google, he aims to avoid the fate of Microsoft - a highly lucrative, occasionally innovative giant, but one with a seemingly weak grip on the future.

The creation of Alphabet helps to address some of Google's problems immediately. The instant share price bump comes on the heels of an even bigger one last month, prompted by a pledge of "great care regarding resource allocation", and means an equity gain of more than 20pc for investors so far this year. Some talented Google software experts sitting on options might also be less likely to jump ship early.

Page's blue-sky tendencies should also be less of a problem for hard-headed investors. The problems of Alphabet's for-profit business are now the domain of Sundar Pichai, the new chief executive of Google. The fundamental mobile challenge, YouTube's intensifying battle with Facebook for online video advertising dollars and myriad regulatory problems will be faced day-to-day by the 43-year-old Indian. A new holding company will not provide him with answers, however.

Page and the Alphabet board are meanwhile free to devote time - and Google cash - to futuristic ventures such as Calico, the longevity biotech business apparently inspired by the Google founders' personal fears of degenerative diseases. Page suffers from a nerve problem that can paralyse his vocal cords, and Sergey Brin, his co-founder, has donated more than $100m to research into Parkinson's disease, which he has a 50pc chance of developing.

Page has spoken admiringly recently of one of corporate America's elder statesmen, Warren Buffett, and the structure of separate businesses with a common culture he has built at Berkshire Hathaway. Comparisons between Alphabet and Buffett's conservative investing in profitable established brands do not stand up to much scrutiny, though.

In week one, Google's new owner looks more like a highly adventurous venture capital firm, albeit one that is funded not by institutions or wealthy individuals but by a massively profitable collection of advertising businesses.

The investments Alphabet is making are in new, risky technology businesses rather than Heinz baked beans or Coca-Cola and lie outside even Google's comfort zone on the web.

The only certainty at the moment is that under the new structure, it will be easier to count the costs.